Central Office on ICD-9-CM - www.ahacentraloffice.org/
The International Classification of Diseases, Ninth Revision, Clinical Modification, ICD-9-CM, is a classification system that groups related disease entities and procedures for the reporting of statistical information.

Diagnosis Codes, International Classification of Diseases - www.cdc.gov/nchs/about/otheract/icd9/abticd9.htm